07/01/2016 07:58 GMT | Updated 07/01/2017 05:12 GMT

Three Days of Terror: The Charlie Hebdo Attacks

Andrew Milligan/PA Wire

Paris, Friday 13 November. It's around 6pm and we're finishing the last interview of the day at Good Light Studio, a converted print factory on Rue Godefroy Cavaignac in the 11ème arrondissement. At the far end of the street, where it meets the buzzy thoroughfare of the Rue de Charonne, young people gather at La Belle Equipe, a lively neighbourhood bar with a pleasant terrace on the street.

In three and a half hours two young Frenchmen will empty their assault rifles into the throng at the Belle Equipe, killing 19. Minutes after that, the massacre at the Bataclan will begin. As midnight approaches a couple of hundred young people will lie bleeding in the darkness of the theatre while heavily-armed policemen wait outside the theatre. Dozens of injured youngsters have already bled out and lie sprawled in the mosh pit under a pall of gunsmoke.

When the shooting is over in the small hours of Saturday morning the man now sitting in front of me - Professor Jean Pierre Tourtier - will move among the wounded, triaging with quick efficiency, trying to save as many ebbing lives as he can.

Right now, sitting in our little bohemian studio we know none of this. Right now Tourtier - Chief Medic of the Paris Fire Brigade - is wrapped in the yellow glow of the huge soft-light umbrella, facing my two video cameras. I'm surprised to see tears glistening behind his spectacles. His face quivers slightly as he struggles to maintain his composure. He is after all a soldier, a member of France's armed forces like all Paris firefighters. And now I'm surprised to feel a prickle of tears in my eyes too, as his parting words hit home...

I'm interviewing Tourtier for a documentary on the Charlie Hebdo attacks, which happened 10 months earlier in January. Tourtier was at an emergency medics' conference not far from the Charlie Hebdo office when a colleague, Patrick Pelloux, got a text saying there was gunfire in the offices of the satirical magazine. Tourtier and Pelloux hopped on a scooter and were the first rescuers to arrive at the scene of the Charlie Hebdo massacre, in a quiet side-street in the 11eme arrondissement. Figuring that in case the terrorists were still in the building it would be best to maximize their chances by taking different routes, Tourtier ascended in the elevator to Charlie Hebdo's second-floor office while Pelloux took the stairs.

At the time Tourtier had never spoken in public about the aftermath of the massacre at Charlie Hebdo. His precise descriptions of what he saw had a barely-suppressed intensity that took me by surprise: "The first thing I remember, even before I entered the Charlie Hebdo office - was the smell. A smell that was a mix of gunpowder and blood - that metallic smell of blood. Then I saw a pile of bodies. And someone at the back of the meeting room said - in a voice that was almost gentle - 'Monsieur, s'il vous plaît, aidez-moi'."

Tourtier went over everything he saw and felt with unsparing honesty. The small meeting-room at Charlie Hebdo was a mass of bodies, many with terrible wounds. The floor was awash with blood. Tourtier ran out of tourniquet material to staunch the bleeding and asked the surviving members of Charlie's editorial staff to give him their belts. When he called back to his base for backup the Fire Brigade dispatcher could not believe what he was hearing. We later recovered the audio recording of Professor Tourtier's call:

- This is Tourtier, I'm on site at Charlie Hebdo. We've got five critically wounded and 10 deceased.

- Two deceased?

- Ten

- Ten deceased?

- Ten deceased, yes

- Wow. Ten?? One-zero? Two times five??

- One-zero. Send trauma teams right now!

The dispatcher's incredulity was understandable. In January 2015 Paris had never experienced a terrorist attack of this magnitude. The crisis lasted three days and left 17 dead. It would be another 10 months before that total was eclipsed by the November 13 massacres, with 89 dead at the Bataclan theatre alone, just 500 yards down the boulevard from Charlie Hebdo.

Tourtier's parting words in his interview earlier that November evening electrified the studio and gave me renewed hope for France's struggle with its contingent of home-grown terrorists: "Yes, the terrorists will risk their lives for their ideas... But there are many French people," and now Tourtier's voice shook with a mixture of sentiment and steely resolve: "Medics, firefighters, gendarmes, policemen, ordinary citizens... who are also ready to risk their lives for their ideas." When Tourtier had finished his eyes were bright with tears. I cut the cameras and thanked him. As we were chatting after the interview I remarked casually that it wouldn't be long before the next attack, as I thought that in terms of security nothing had changed since January and the Charlie Hebdo attacks. There was nothing to prevent another, even deadlier attack from happening.

We said goodbye. Twenty minutes later I walked out of the studio onto Rue Godefroy Cavaignac and turned left towards the Voltaire metro station. Two hundred yards behind me at La Belle Equipe a small, friendly crowd was gathering at the bar, mostly waiters and waitresses from nearby restaurants, ordering what for many them would be their last few drinks. It was nearly seven o'clock.

Three Days of Terror: The Charlie Hebdo Attacks, first broadcast on BBC Two, is now available on iPlayer here.

Watch a clip here.